UMaine offshore wind team engaged in international race to use lasers to gauge ocean wind speeds

ORONO, Maine — The University of Maine is in the midst of an international race to develop a new system to measuring winds high above the oceans and advance the push for offshore wind power.

UMaine’s Advanced Structures and Composites Center is working on a buoy-based light detection and ranging system, or LiDAR, which it hopes to deploy in the Gulf of Maine by late May or early June, according the center’s director, Habib Dagher.

The technology uses a laser to measure the speed of tiny particles in the air, gauging the wind speed up to 600 feet above the water’s surface. The university partnered with Vermont-based NRG Systems to build the LiDAR, which will be mounted to a retrofitted buoy 10 feet in diameter.

That system’s wind data will be used to determine where future offshore wind farms could be placed, and could one day develop into a business, Dagher said during a recent interview.

“The offshore wind industry is growing dramatically across the world right now,” Dagher said.

A UMaine team is working to harness the Gulf of Maine’s winds by 2030, placing a full-scale wind farm of about 170 turbines, each taller than the Washington Monument, in the Gulf of Maine. That farm would bring 5 gigawatts, or the equivalent of about five nuclear power plants, of wind energy to Maine’s shore, Dagher has said. Other groups in the United States and abroad are working on offshore wind projects of their own.

UMaine’s School of Marine Science’s Physical Oceanography Group has been measuring wind, wave and atmospheric conditions in the Gulf of Maine for more than a decade, but that wind data is gathered just 10 feet above the water by an anemometer. That data is used by many mariners and gives UMaine a leg up in the global race to implement these systems, Dagher said.

Based on the low-level wind data, groups pursuing wind development projects can calculate what the wind would be above 200 feet, where winds typically are stronger, but investors want to see solid data when considering whether to get involved in large-scale wind projects, said Neal Pettigrew, a professor of physical oceanography.

“We know what the wind speed has been at 10 feet above the Gulf of Maine,” Dagher said, “but that data isn’t bankable.”

When gathering data for an on-shore wind farm, a tower can be built with an anemometer at the top to get wind readings. But a tower isn’t a viable or cost-effective option in deep water, Dagher said.

Groups worldwide are eyeing the possibilities of LiDAR as an inexpensive, mobile option for determining wind energy development potential in the world’s oceans.

Ecofys, an environmental and renewable energy consulting group based in the Netherlands, recently sent out a global press release stating that it was working on a LiDAR systems of its own to increase the effectiveness of future wind projects. Ecofys said it expects will increase the value of Dutch wind farms by more than $1 million euros, or about $1.3 million U.S. dollars.

AXYS Technologies, a Canadian company, is working on a floating LiDAR system of its own.

On the ocean, it’s not as simple as strapping a LiDAR to a buoy, Dagher said. Because the motion of the waves would cause the laser to move and throw off measurements, a stabilizer system had to be designed to hold the LiDAR steady while the buoy moves.

The LiDAR system also consumes a significant amount of energy, according to Dagher. To power the system, a series of six small wind turbines and six solar panels will be attached to charge the battery. With these panels and small turbines, the buoy can operate unmanned in the ocean for 6 months to a year.The whole buoy system will weigh more than 5,000 pounds.

The stakes could be high, with an increasing number of groups in the U.S. and abroad looking to the seas as a means of energy production, Dagher said.

If the university has a successful launch of its first LiDAR buoy, it could lead the world in creating a new business that produces such systems for groups exploring wind development along the U.S. east coast or across the globe, according to Dagher. Each unit could be sold for between $1 million and $1.5 million, he said.